1. Field of the Invention
This invention is directed in general to security systems and in particular, to a wireless security system in which a control unit which operates with a plurality of peripheral devices, is capable of receiving and verifying coded signals from each of the plurality of peripheral devices. The peripheral devices transmit the coded signals using a different data frame pattern during each transmission.
2. Prior Art
Transmitter-receiver controller systems are widely used for remote control and/or actuation of devices or appliances such as garage door openers, gate openers, and security systems. For example, most conventional security systems use a transmitter-receiver combination to monitor selected areas. In such conventional security systems, all the peripheral devices such as sensors, and the control unit operate using the same identification code, so that only those devices belonging to a particular installed security system on the premises can operate with each other. Other devices which operate using a different identification code, would be ignored. In more complicated systems, various groups of peripheral devices may be assigned to different zones, each of which is monitored for quick identification in the event of a security breach.
Such conventional security systems provide several security risks. First, since a single, fixed identification code is utilized, the identification code may be detected by a hostile user, and subsequently used to disarm the control unit. Secondly, since all the peripheral devices operate using the same identification code, back-up or secondary sensors are rendered useless in the event that the control circuitry for the primary sensor is disarmed.
Accordingly, there is a need in the technology for a security system which provides increased security by having a control unit which operates with a number of peripheral device, each having different identification codes which cannot be easily detected. In addition, there is a need for a security system which facilitate the implementation of secondary sensors which can function despite of detection of primary sensors.